var oul = document.getElementById('menu_ul');
var aLi = oul.getElementsByTagName('li');
var aDiv = document.getElementsByClassName('divli');
for(var i = 0; i < aLi.length; i++){
	aLi[i].index = i;
	aLi[i].onclick = function(){
		
		for(var j = 0; j < aLi.length;j++){
			aLi[j].className = ' ';
			aDiv[j].style.display = 'none';
		}
		this.className = 'ctn_menu_active';
		aDiv[this.index].style.display = 'block';
	}
}